This is a proposal for funds to support the second FASEB Summer Research Conference on Molecular Aspects of Metastasis (Leo T. Furcht, University of Minnesota, Chair and George R. Martin, National Institute on Aging, Co- Chair). The first conference was attended by about 100 scientists and was rated very highly by the attendees in their evaluation questionnaires. Metastasis is a critical event in the natural history of cancer responsible for most deaths. Numerous investigators have done much to define the steps in metastases, oncogenes that are able to activate the metastatic phenotype and the role of host factors such as growth factors and matrix molecules. Much of this work has been carried out with lines of melanoma cells and has utilized i.v. injection of these cells to score metastatic activity. This conference will distinguish itself by emphasizing the unique aspects of the major human cancers--breast, colon, lung, and prostate--in a session organized by Jim Mulshine, National Cancer Institute, and Marc Lippmann. Factors associated with cancer progression and the role of suppressor genes will also be emphasized. Four sessions will deal with metastatic cells including molecular and cellular behavior. One of these sessions will involve short presentations will be added to each session's program to ensure broad participation. Approaches to the pharmacological modulation of metastases will be organized by Olden and Gottesman. New information on angiogenesis and Kaposi's sarcoma will be discussed. Thus, this meeting should join persons working in diverse areas of cancer research with researchers studying metastasis and assist in developing methods to suppress the spread of important human cancers.